Turbine-bucket.



TURBINE BUCKET.

APPLIOATION FILED AUG..15. 1907. 974.160. Patented Nov. 1, 1910.

IrwVenbor-g oql'Fr-'ed H. udiich,

narrow mouth of the vundercutgroove in UNITED STATES PArENr oEEIoE.

l. ALIg'RED H. KUDLICH, 0F LYNN, MASSACHUSETTS, .ASSIGNOR T0 GENERALELECTRIC COMPANY, A CORPORATION F NEW YORK.

TURBINE-BUCKET.

Specification of Letters Patent.

' Application ined August-15, 1907. serial No. 588,639.

Patented Nuv.1,'191o.

To all whom tt may concern.' f I Be it known that I, ALFRED H. KUDLIGH,

a citizen of the United States, residing at bin'es, in whichftherotatingelement is provided with a' plurality of 'curved blades upon which thesteam lmpinges; It is customary, in large units, to make the bladesseparate and secure them in rows upon the periphery of the bucket wheel.A common Inode of fastening the bucket is to cut away one end of it tofrm a dovetailed tenon which is inserted' insan undercut groove in theedge of thebucket wheel, or in a segment which. is afterwardattached tothe wheel. The cutting of the tenon wastes a rconsiderable quantity-ofthe metal, and one of theobjectsof my invention is to prevent thiswaste. Furthermore, owingfto the thinning ,of the bucket toward itsedges, the tips of the `\do'vetailed ten`onare its narrowest and weakesportions, whereas the parts which 'engage .the lowest part of the sidewalls of the undercutg'roove should be the strongest, because at Athatpoint there is a greater thickness of metal in the wheel to resistcentrifugal force.` Then vit is reme`m-v bered that a bucket weighingone pound mounted on the vperiphery of a. twelve foot wheel making 600revolutions per minute exerts a centrifugal force of 736 pounds, thenecessity for a strong and unyielding fastenina becomes apparent. Afurther object, therefore, of my invention, is to strengthen the partswhich retain the bucket in the groove.

I accomplish the results aimed at by slotting the sides of the bucket intoward the middle thereof, leaving sufficient metal between the innerends ofthe slots to fill the the bucket-wheel or segment. The horns.produced these slots arethen-,bent in a forward and backward direction;beyond the plane of'lthe bucket, and preferably toward th concave sideof the bucket so that their outer'ed'ges'are parallel and stand justfar' enough apart to t against the side walls of the undercut portion ofthe groove. The

customary spacing blocks are interposed between the bases ofthe adjacentbuckets.

In the aceomp'an'yin" drawings, Figure 1 is a side elevation, art y insection, of a portion of a bucket vv eel and a ewrbucltets se curedthereto after the manner of my invention; Fig. 2 is a. longitudinalcrossf'section thereof, on' the line 2 2, Fig. ltFig. is a radialcross-section on the' line B-3, Fig, 2; and Fig. 4 is a perspective viewer eue of the buckets y The wheel 1 has an undercut groove in itsperiphery. At some convenient point the side of the wheel is cut away tofoi-in a lat eral inlet to said groove. "Ths inletis closed by a block2, conforming to theshape of the groove and secured by a transverse.rivet 3.

The bucket thas two eppostely located slots a 5 extending into its'sides parallel with and near its bottom. The portion of the neck orshank 6 of the bucket petween the inner 'ends of said slots is just wideenough tol fit snugly in the narrow mouth of the underout groove in thewheel. The horns 7 formed on the flower end of the, neck or shank bycutting these slots are then bent beyond the plane of the bucket andpreferably both toward the concave side of the bucket until their Youtersides stand parallel with each other; that is, transverse to a linejoining the outer edges of the bucket.r The outer walls of the grooveare ofa the roper height to recevetbese horns, so that tile-y lie snuglybetween the bottom of the roove and the overhanging metal above. heupper edges of the horns aiforda long bearing' surface to resist theradial strain on lthe bucket dueto centrifugal force. p y g The bucketsare assembled in ithegroojve b y removin the block '2 and slipping thebuckets in tterally through the inlet and then sliding them along thegroove. Space ing or filling blocks 8 are interposed between adjacentbuckets, fitting(- also between the horns 7. If desired, the pitch mayberegulated by machining oit the tips of the horns so that the length ofthe horns is the same on all the buckets. 4The tips of the horns on onevbucket are then abutted against the convex back of the next bucket,thus spacing all the buckets at e ual distances. The lilling between thebucrets may then be effected by lpouring in melted tvpe-metal orthellike, instead of using solid blocks slipped in alternately with thebuckets.

It will be seen that the above-described construction cuts down stressesin the blade or bucket to something like and affords greater utilizationof stock by increase of holding surface thereby affording a muchstronger fastening for the buckets.

In accordance with the provisions of the patent statutes, I havedescribed the principle of operation of my device together with theapparatus which I now consider to represent the best embodiment thereof;but I desireto have it understood that the apparatus shown is onlyillustrative, and that the invention can be carried out by other means.

NVhat I claim as new and desire to secure by Letters Patent of theUnited States, is,-

1. A turbine bucket, the middle portion of which. is. thicker than itsedges, said bucket having its base provided with a neck of less widththan the bucket and of the same thickness as the. adjoiningportion ofthe body of the bucket, and horns extending from the base in a directiontransverse to a line joining the outer edges of the bucket.

2. A curved turbine bucket the middle portion of which is thicker thanits edges, said bucket having its base formed from a neckprojecting'from its middle portion and horns on the outer end of theneck extending in a forward and backward direction beyond ,the body ofthe bucket.

3. A curved turbine bucket the middle portion of which is thicker thanits edges, said bucket having its base provided with a neck projectingfrom said middle portion that is of less width4 than the bucket andhorns extending from the outer end of the neck on the concave side ofthe bucket with their outer faces parallel.

al. The combination with a turbine Wheel having an undercut groove, of aturbine bucket having forwardly extending horns whose outer sides areparallel and whose upper edges lit under the over-hanging portion ofsaid groove.

5. The combination with a turbine Wheel having an undercut groove, ofabucket provided with holding members which extend along said groovebeyond the plane of said bucket and engage the walls of the groove. G.The combination with a turbine wheel having an undercut groove, ofabucket having horns at its lower endv which extend along said groove.

7. The combination with a turbine wheel having an undercut groove, of aplurality of buckets, each having horns which extend along said groove,and abut against thc next bucket.

8. The combination with a turbine wheel having an undercut groove, of aplurality of buckets each having horns which extend along said groove,and filling between said buckets and between said horns.

9. The combinationwith a turbine Wheel having an undercut groove, of aplurality of buckets each having horns lying in said groove and abuttingagainst the vnext bucket, and fusible material filling the spacesbetween said buckets.

10. A turbine bucket having a substantially central neck or shank ofless width than the portions of the bucket above and below said neck orshank, one of said portions being provided with parallel retaining hornsextending 1n a direction transverse to the face of the bucket.

ll.A A curved turbine bucket having a body the middle portion of whichis thicker than its edgesa substantially centrally arranged neckprojecting downward from the body which is of less Width than the bodyand has the same thickness and curvature as the corresponding part ofsaid body, and horns extending from each side of the lower end of theneck in a direction transverse to the faces of the bucket.

l2. A. curved turbine bucket having a body the middle portion of whichis thicker than .its edges, a neck forming an extension from the middleportion of the bodythat is of less width than said body, and hornsprojecting from each side of the neck in a direction transverse to thefaces of the bucket, the distance between the outer faces of the hornsbeing greater than the `width of the neck.

13. The combination with a turbine wheel having an undercut groove inits periphery, o f buckets having their bases secured in the groove,eachbase comprising a neck which engages the narrow portion of thegroove and horns that project from the neck and extend along the groovein engagement with the overhanging walls of said groove.

In witness whereof, I have hereunto set my hand this twelfth day ofAugust, 1907.

ALFRED H. KULIC'H. iVitnesses ALEX. F. MACDONALD, JOHN A. MCMANUS, Jr.

